Ampicillin stability over 14 years - (Oct/05/2007 )

Maybe this is a very stupid question..but still.

I'm planning to perform a standard cloning procedure with a vector carrying an ampicillin resistance.

I need to make LB-plates with a standard ampicillin concentration for the delective growth of transformants.Since my University lacks a lot of money (or just don;t want to spend it) we have a ampicillin powder from 1993!!i know its solid, so stable. Keeping it on RT for a while is no problem, but this is 14 years old.Also because it is used in that time multiple time (getting in and out of +4) it doesn;t feel safe to use.Doesn anybody know if this could hurt?

-PRETEGM-

make a LB broth add this ancient amp and put non-resistant bacteria, grow for at least 16 hr at 37, if media is clean and in control if it is turbid, you have found out a miracle. if it indeed works let me know which company that amp belongs to

-Calvin*-

QUOTE (Calvin* @ Oct 5 2007, 06:12 AM)

make a LB broth add this ancient amp and put non-resistant bacteria, grow for at least 16 hr at 37, if media is clean and in control if it is turbid, you have found out a miracle. if it indeed works let me know which company that amp belongs to

I don't think it would be a miracle. I think it could work still fine. But definitively it most be tested before used as you say.

-aztecan princess-

if dry it should be okay. But still do conduct the test Calvin* suggested.

-perneseblue-

QUOTE (PRETEGM @ Oct 5 2007, 05:32 AM)

Maybe this is a very stupid question..but still.

I'm planning to perform a standard cloning procedure with a vector carrying an ampicillin resistance.

I need to make LB-plates with a standard ampicillin concentration for the delective growth of transformants.Since my University lacks a lot of money (or just don;t want to spend it) we have a ampicillin powder from 1993!!i know its solid, so stable. Keeping it on RT for a while is no problem, but this is 14 years old.Also because it is used in that time multiple time (getting in and out of +4) it doesn;t feel safe to use.Doesn anybody know if this could hurt?

I would have a trial if there is no visible hydration or change in color;

-The Bearer-

Thanks for the suggestions.

I did as mentioned by Calvin and it showed different results. I made 3 broths of which one was "clean" and 2 were slightly turbid. So I thinl I will order some new ampicillin!